1. Technical Field
This technology relates generally to a bioactive coating on a medical device and methods of making and using the same, and more particularly to an intracranial aneurysm coil having a polymer coating on selected surfaces of the coil.
2. Background Discussion
Subarachnoid hemorrhage from intracranial aneurysm rupture remains a devastating disease. Endovascular occlusion of ruptured and unruptured intracranial aneurysms using Guglielmi Detachable Coil (GDC) technology has gained worldwide acceptance as a less-invasive treatment alternative to standard microsurgical clipping. However, critical evaluation of the long-term anatomical results of aneurysms treated with metal coils shows three limitations. First, compaction and aneurysm recanalization can occur. This technical limitation is more often seen in small aneurysms with wide necks and in large or giant aneurysms. Second, the standard platinum metal coil is relatively biologically inert. Research relating to methods of enhancing the biological activity of metal coils highlights the increased interest in finding innovative solutions to overcome these present biological limitations of the conventional metal coil system.
Polymeric coatings carrying a bioactive agent have been used to impart bioactivity to implantable devices (e.g., stents). However, when a polymeric coating is formed on a spiral coil, often times, the grooves of the spiral coil are coated along with the outer surface of the coil, causing the mechanical flexibility to be compromised, which is undesirable. Further, for a spiral coil to be spatially compatible with a vascular lumen in the brain, sometimes it is important to limit the diameter of a coil to a certain size since it is constrained by the inner diameter of the microcatheter used for placing the coil.
The technology of the present disclosure addresses the foregoing limitations of spiral intracranial aneurysm coils.